The cities with the least competitive Medicare Advantage markets

Lawton, Okla. has the least competitive Medicare Advantage market in the country, according to a study from the American Medical Association published Nov. 1. 

Humana has 88 percent of the Medicare Advantage market in the city of around 90,000 in the Southwest part of the state. 

The AMA published a report comparing competition among payers in commercial, exchange and Medicare Advantage markets at the state and city level. 

Here are the cities where one payer controls more than 70 percent of the local market. 

Over 85 percent 

• Lawton, Okla. — Humana, 88 percent market share 
• Vallejo, Calif. — Kaiser Permanente, 87 percent market share 
• Napa, Calif. — Kaiser Permanente, 86 percent market share 
• Casper, Wyo. — UnitedHealthcare, 86 percent market share 

Over 80 percent 

• Wenatchee, Wash. — Carle Health, 82 percent market share 
• Salinas, Calif. — Montage Health, 80 percent market share 
• Valdosta, Ga. — UnitedHealthcare, 80 percent market share 
• Wichita Falls, Texas — UnitedHealthcare, 80 percent market share 

Over 75 percent 

• Santa-Rosa-Petaluma, Calif. — Kaiser Permanente, 79 percent market share 
• Dubuque, Iowa — Medical Associates, 77 percent market share 
• Waterloo-Cedar Falls, Iowa — UnitedHealthcare, 77 percent market share 
• Jacksonville, N.C. — Humana, 77 percent market share 
• Logan, Utah-Id. — UnitedHealthcare, 77 percent market share 
• El Centro, Calif. Bright Health, 75 percent market share 
• Billings, Mont. — Humana, 75 percent market share 
• Bloomsburg-Berwick, Pa. — Geisinger, 75 percent market share 
• Burlington-South Burlington, Vt. — UnitedHealthcare, 75 percent market share 

Over 70 percent 

• Jefferson City, Mo. — UnitedHealthcare, 73 percent market share 
• Las Cruces, N.M. — UnitedHealthcare, 72 percent market share 
• St. Joseph, Mo.-Kan. — UnitedHealthcare, 71 percent market share 
• Wilmington, N.C. — Humana, 71 percent market share
• San Francisco-Oakland-Berkeley, Calif. — Kaiser Permanente, 70 percent market share 
• Ocean City, N.J. — Aetna, 70 percent market share 
• New Bern, N.C. — Humana, 70 percent market share 
• Milwaukee-Waukesha, Wisc. — UnitedHealthcare, 70 percent market share